tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * driver/base/topology.c - Populate sysfs with cpu topology information
3 *
4 * Written by: Zhang Yanmin, Intel Corporation
5 *
6 * Copyright (C) 2006, Intel Corp.
7 *
8 * All rights reserved.
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
18 * NON INFRINGEMENT. See the GNU General Public License for more
19 * details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 *
25 */
26#include <linux/sysdev.h>
27#include <linux/init.h>
28#include <linux/mm.h>
29#include <linux/cpu.h>
30#include <linux/module.h>
31#include <linux/hardirq.h>
32#include <linux/topology.h>
33
34#define define_one_ro_named(_name, _func) \
35static SYSDEV_ATTR(_name, 0444, _func, NULL)
36
37#define define_one_ro(_name) \
38static SYSDEV_ATTR(_name, 0444, show_##_name, NULL)
39
40#define define_id_show_func(name) \
41static ssize_t show_##name(struct sys_device *dev, \
42 struct sysdev_attribute *attr, char *buf) \
43{ \
44 unsigned int cpu = dev->id; \
45 return sprintf(buf, "%d\n", topology_##name(cpu)); \
46}
47
48#if defined(topology_thread_cpumask) || defined(topology_core_cpumask) || \
49 defined(topology_book_cpumask)
50static ssize_t show_cpumap(int type, const struct cpumask *mask, char *buf)
51{
52 ptrdiff_t len = PTR_ALIGN(buf + PAGE_SIZE - 1, PAGE_SIZE) - buf;
53 int n = 0;
54
55 if (len > 1) {
56 n = type?
57 cpulist_scnprintf(buf, len-2, mask) :
58 cpumask_scnprintf(buf, len-2, mask);
59 buf[n++] = '\n';
60 buf[n] = '\0';
61 }
62 return n;
63}
64#endif
65
66#ifdef arch_provides_topology_pointers
67#define define_siblings_show_map(name) \
68static ssize_t show_##name(struct sys_device *dev, \
69 struct sysdev_attribute *attr, char *buf) \
70{ \
71 unsigned int cpu = dev->id; \
72 return show_cpumap(0, topology_##name(cpu), buf); \
73}
74
75#define define_siblings_show_list(name) \
76static ssize_t show_##name##_list(struct sys_device *dev, \
77 struct sysdev_attribute *attr, \
78 char *buf) \
79{ \
80 unsigned int cpu = dev->id; \
81 return show_cpumap(1, topology_##name(cpu), buf); \
82}
83
84#else
85#define define_siblings_show_map(name) \
86static ssize_t show_##name(struct sys_device *dev, \
87 struct sysdev_attribute *attr, char *buf) \
88{ \
89 return show_cpumap(0, topology_##name(dev->id), buf); \
90}
91
92#define define_siblings_show_list(name) \
93static ssize_t show_##name##_list(struct sys_device *dev, \
94 struct sysdev_attribute *attr, \
95 char *buf) \
96{ \
97 return show_cpumap(1, topology_##name(dev->id), buf); \
98}
99#endif
100
101#define define_siblings_show_func(name) \
102 define_siblings_show_map(name); define_siblings_show_list(name)
103
104define_id_show_func(physical_package_id);
105define_one_ro(physical_package_id);
106
107define_id_show_func(core_id);
108define_one_ro(core_id);
109
110define_siblings_show_func(thread_cpumask);
111define_one_ro_named(thread_siblings, show_thread_cpumask);
112define_one_ro_named(thread_siblings_list, show_thread_cpumask_list);
113
114define_siblings_show_func(core_cpumask);
115define_one_ro_named(core_siblings, show_core_cpumask);
116define_one_ro_named(core_siblings_list, show_core_cpumask_list);
117
118#ifdef CONFIG_SCHED_BOOK
119define_id_show_func(book_id);
120define_one_ro(book_id);
121define_siblings_show_func(book_cpumask);
122define_one_ro_named(book_siblings, show_book_cpumask);
123define_one_ro_named(book_siblings_list, show_book_cpumask_list);
124#endif
125
126static struct attribute *default_attrs[] = {
127 &attr_physical_package_id.attr,
128 &attr_core_id.attr,
129 &attr_thread_siblings.attr,
130 &attr_thread_siblings_list.attr,
131 &attr_core_siblings.attr,
132 &attr_core_siblings_list.attr,
133#ifdef CONFIG_SCHED_BOOK
134 &attr_book_id.attr,
135 &attr_book_siblings.attr,
136 &attr_book_siblings_list.attr,
137#endif
138 NULL
139};
140
141static struct attribute_group topology_attr_group = {
142 .attrs = default_attrs,
143 .name = "topology"
144};
145
146/* Add/Remove cpu_topology interface for CPU device */
147static int __cpuinit topology_add_dev(unsigned int cpu)
148{
149 struct sys_device *sys_dev = get_cpu_sysdev(cpu);
150
151 return sysfs_create_group(&sys_dev->kobj, &topology_attr_group);
152}
153
154static void __cpuinit topology_remove_dev(unsigned int cpu)
155{
156 struct sys_device *sys_dev = get_cpu_sysdev(cpu);
157
158 sysfs_remove_group(&sys_dev->kobj, &topology_attr_group);
159}
160
161static int __cpuinit topology_cpu_callback(struct notifier_block *nfb,
162 unsigned long action, void *hcpu)
163{
164 unsigned int cpu = (unsigned long)hcpu;
165 int rc = 0;
166
167 switch (action) {
168 case CPU_UP_PREPARE:
169 case CPU_UP_PREPARE_FROZEN:
170 rc = topology_add_dev(cpu);
171 break;
172 case CPU_UP_CANCELED:
173 case CPU_UP_CANCELED_FROZEN:
174 case CPU_DEAD:
175 case CPU_DEAD_FROZEN:
176 topology_remove_dev(cpu);
177 break;
178 }
179 return notifier_from_errno(rc);
180}
181
182static int __cpuinit topology_sysfs_init(void)
183{
184 int cpu;
185 int rc;
186
187 for_each_online_cpu(cpu) {
188 rc = topology_add_dev(cpu);
189 if (rc)
190 return rc;
191 }
192 hotcpu_notifier(topology_cpu_callback, 0);
193
194 return 0;
195}
196
197device_initcall(topology_sysfs_init);